Hi Alex,
This thread seems to be a duplicate but I'll post here too a method that can save time for people entering lots of dates. After the one-time setup, this is just a menu pick or keyboard shortcut.
If you often enter dates here is a way that can save you some time.
(This is a one-time setup. Using it thereafter is just a menu pick or keyboard shortcut.)
Open Automator (in your applications folder) and choose Service as document type;
Drag Run AppleScript action from the left over into the right pane:
Copy this script and paste it into the right pane (replacing what's there):
on run
set date_ to ((current date) as string)
set the clipboard to the date_
end run
After clicking the hammer, the right pane should now look like this:
Save the Automator Service as "Get Date" or whatever you want to call it.
You only need to do these setup steps steps ONCE.
Now, whenever you need to input the date, just choose Get Date in the Numbers Services menu.
And paste into the cell where you need it with command-v.
If you don't like the services menu you can also assign Get Date to a keyboard shortcut, so you would type your keyboard shortcut followed by command-v.
SG